Carboxymethyl Cellulose Films Research Articles

Stretching of Carboxymethyl Cellulose Films with Dispersed Single-Wall Carbon Nanotubes

Stretching of Carboxymethyl Cellulose Films with Dispersed Single-Wall Carbon Nanotubes

The anti‐adhesive effect of thermally cross‐linked gelatin film and its influence on the intestinal anastomosis in canine models

To generate a more effective and safer anti-adhesive material, we have developed a new type of thermally cross-linked gelatin film. In this study, we preclinically examined the anti-adhesive efficacy of this film and evaluated the possibility applying the film safely onto fresh intestinal anastomoses, compared with hyaluronate and carboxymethyl-cellulose (HA/CMC) film. Using a canine adhesion model, the degree of adhesion for each film was evaluated by adhesion scoring systems and histological observation. Three weeks after surgery, only the gelatin film showed significantly superior anti-adhesive effects compared to the control (no treatment), in particular, exhibiting excellent re-peritonization. Next, in a canine anastomosis model, the anastomoses were wrapped directly by each film and the bursting pressures of the anastomoses were examined 3 and 7 days after surgery. The gelatin film did not significantly affect either the bursting pressures or the healing process, compared with the control. However, the HA/CMC film significantly decreased the bursting pressures measured at 3 days after surgery. In conclusion, the thermally cross-linked gelatin film had satisfactory anti-adhesive effects with excellent re-peritonization. It could be safely applied to intestinal anastomoses without decreasing the bursting pressures. The gelatin film is considered to be quite favorable as an anti-adhesive material.

Biodegradation of PVP–CMC hydrogel film: A useful food packaging material

Hydrogels can offer new opportunities for the design of efficient packaging materials with desirable properties (i.e. durability, biodegradability and mechanical strength). It is a promising and emerging concept, as most of the biopolymer based hydrogels are supposed to be biodegradable, they can be considered as alternative eco-friendly packaging materials. This article reports about synthetic (polyvinylpyrrolidone (PVP)) and biopolymer (carboxymethyl cellulose (CMC)) based a novel hydrogel film and its nature of biodegradability under controlled environmental condition. The dry hydrogel films were prepared by solution casting method and designated as ‘PVP–CMC hydrogel films’. The hydrogel film containing PVP and CMC in a ratio of 20:80 shows best mechanical properties among all the test samples (i.e. 10:90, 20:80, 50:50, 80:20 and 90:10). Thus, PVP–CMC hydrogel film of 20:80 was considered as a useful food packaging material and further experiments were carried out with this particular hydrogel film. Biodegradation of the PVP–CMC hydrogel films were studied in liquid state (Czapec-Dox liquid medium+soil extracts) until 8 weeks. Variation in mechanical, viscoelastic properties and weight loss of the hydrogel films with time provide the direct evidence of biodegradation of the hydrogels. About 38% weight loss was observed within 8 weeks. FTIR spectra of the hydrogel films (before and after biodegradation) show shifts of the peaks and also change in the peak intensities, which refer to the physico-chemical change in the hydrogel structure and SEM views of the hydrogels show how internal structure of the PVP–CMC film changes in the course of biodegradation.

Carboxymethyl cellulose film from durian rind

Cellulose from durian rind was converted to carboxymethyl cellulose (CMCd) by carboxymethylation using sodium monochloroacetate (SMCA) and various sodium hydroxide (NaOH) concentrations (20–60 g/100 mL). The chemical structure of the cellulose and resulting polymers was then characterized using Fourier transform infrared spectroscopy (FTIR). Then, the properties of the CMCd materials were investigated. The optimum condition for carboxymethylation was found to be 30 g/100 mL NaOH, which provided the highest viscosity and degree of substitution (DS = 0.87). Crystallinity of CMCd was found to decline after synthesis. The L* value of the CMCd decreased with increasing NaOH concentrations (20–40 g/100 mL). The trend of the a* and b* values varied inverses to the L* values. The CMCd films were prepared and tested, and the highest tensile strength (140.77 MPa) and WVTR (220.85 g/day·m2) were found using the 30 g/100 mL NaOH-synthesized CMCd film. The percent elongation at break of the different CMCd films was not to significantly differ.

Dielectric characterization and catalytic activity studies of nickel chloride doped carboxymethyl cellulose films

Cast technique was used to prepare films of sodium carboxymethyl cellulose (CMC) doped with different ratios of NiCl2·6H2O in the range of 0–40Ni2+wt.%. Thermal analysis (DTA) in the range of 25–600°C and dielectric properties in the temperature range of 30–150°C and frequency range of 0.1–100kHz were measured for the prepared samples. DTA analysis showed new exothermic peaks which were attributed to structural phase transitions. Different molecular motions are separated via dielectric relaxation spectroscopy. In the high temperature range (higher than 100°C), the σ-relaxation, which is associated with the hopping motion of ions through polymer material, was detected. The detailed analysis of the results showed that the dielectric dispersion consists of both dipolar and interfacial polarization. Measurements of ac conductivity as a function of frequency at different temperatures indicated that the correlated barrier hopping model (CBH) is the most suitable mechanism for the ac conduction behavior.The catalytic activity of CMC doped with Ni2+ was tested in the reduction of the hazardous pollutant 4-nitrophenol to the functional 4-aminophenol with an excess amount of NaBH4. Ni-free CMC did not exhibit any catalytic activity for the studied reaction. However, Ni2+-doped CMC showed a significant catalytic activity that is proportional to the ratio of Ni2+ included in CMC. The activation energy (Ea) was estimated in the temperature range of 25–40°C. The estimated value of Ea decreased with increasing the ratio of Ni2+. Finally, the optimum catalyst mass was found to be ≈0.6g/l.

Structural aspects of polyanion and hydrophobically modified polycation multilayers on hydrophilic or hydrophobic surfaces

Multilayer films of carboxymethylcellulose (CMC), a polyanion, and bromide salts of poly(4-vinylpyridine) quaternized with linear aliphatic chains of 2 (ethyl) and 5 (pentyl) carbon atoms, coded as QPVP-C2 and QPVP-C5, respectively, were fabricated by layer-by-layer (LbL) self-assembly onto Si/SiO2 wafers (hydrophilic substrate) or polystyrene, PS, films (hydrophobic substrate). The films were characterized by means of ex situ and in situ ellipsometry, atomic force microscopy (AFM), contact angle measurements and sum frequency generation vibrational spectroscopy (SFG). Antimicrobial tests were used to assess the exposure of pyridinium moieties to the aqueous medium. In situ ellipsometry indicated that for Si/SiO2 the chains were more expanded than the PS films and both substrates systems composed of QPVP-C5 were thicker than those with QPVP-C2. For dried layers, the alkyl side group size had a small effect on the thickness evolution, regardless of the substrate. At pH 2 the multilayers showed high resistance, evidencing that the build-up is driven not only by cooperative polymer–polymer ion pairing, but also by hydrophobic interactions between the alkyl side chains. The LbL films became irregular as the number of depositions increased. After the last deposition, the wettability of QPVP-C2 or QPVP-C5 terminated systems on the Si/SiO2 wafers and PS films were similar, except for QPVP-C2 on Si/SiO2 wafers. Unlike the morphology observed for LbL films on Si/SiO2 wafers, PS induced the formation of porous structures. SFG showed that in air the molecular orientation of pyridinium groups in multilayers with QPVP-C5 was stronger than in those containing QPVP-C2. The exposure of pyridinium moieties to the aqueous medium was more pronounced when the LbL were assembled on Si/SiO2 wafers.

Employing perichromism for probing the properties of carboxymethyl cellulose films: an expedient, accurate method for the determination of the degree of substitution of the biopolymer derivative

The properties of films of carboxymethyl cellulose, CMC, of different degree of substitution, DS, have been examined by the use of perichromic indicators (probes). The film properties that have been determined are: empirical polarity, ET(33); “acidity”, α; “basicity”, β; and dipolarity/polarizability, π*. This has been achieved by employing the following perichromic probes: 4-nitroaniline, 4-nitroanisole, 4-nitro-N,N-dimethylaniline, and 2,6-dichloro-4-(2,4,6-triphenyl-pyridinium-1-yl)phenolate, WB. The correlations between both ET(33)- or π* and DS were found to be linear; that between β and DS is a second order polynomial; no obvious correlation was found between α and DS. The polarities of CMC films are in the range of those of butyl alcohols. As models for CMC, we have employed cellulose plus CMC of high DS; oxidized cellulose with degree of oxidation = 0.5; sodium glucuronate. The former model behaved akin to CMC, but the plots of the perichromic properties versus DS showed different slopes/intercepts. FTIR data and molecular dynamics simulations on the solvation of WB have shown that this difference can be traced to more efficient hydrogen bonding between the film of the model and the probe. This affects the intra-molecular charge-transfer energy of the latter, leading to different responses to the variation of DS. Based on the excellent linear correlation between ET(33) and DS, for CMC from different origins, we suggest that perichromism is a simple, accurate, and expedient alternative for the determination of DS of the biopolymer derivative.

Carboxymethylcellulose–montmorillonite nanocomposite films activated with murta (Ugni molinae Turcz) leaves extract

► The addition of MMT to CMC films, improve their physicochemical properties. ► Extract of murta as a solvent produce active films with antioxidant properties. ► Murta active compounds plasticized the films modifying the ratio permeability to gases. The functionality of nanocomposite films based on carboxymethylcellulose (CMC) and montmorillonite (MMT) activated with murta ( Ugni molinae Turcz) leaves extract was studied. Films were prepared by casting from film-forming dispersions containing CMC, glycerol (used as plasticizer) and different concentrations of MMT, using water or murta extract as solvent. The addition of MMT increased the tensile strength and the elasticity modulus of the films, and decreased their permeabilities to water vapor, oxygen and carbon dioxide. Besides the antioxidants properties provided to the films, the addition of murta leaves extract changed the gas permeability in different forms according to the MMT content, and plasticized the nanocomposite matrix.

Synthesis and characterization of carboxymethyl cellulose powder and films from Mimosa pigra

AbstractMimosa pigra peel was sun‐dried for 2 days and then ground before being boiled with 30%w/v sodium hydroxide (NaOH) at 100°C for 3 h, washed and then dried at 55°C to constant weight. The cellulose was then synthesized using different NaOH concentrations and monochloroacetic acid (MCA) in isopropyl alcohol (IPA). Effects of various NaOH concentrations on degree of substitution (DS), viscosity and thermal of carboxymethyl cellulose from Mimosa pigra peel (CMCm) were investigated. The increasing of NaOH concentration resulted in increasing DS and viscosity. However, viscosity of CMCm decreased as temperature increased. Thermal properties were studied using differential scanning calorimetry (DSC). The melting point of the samples decreased as %NaOH increased. The effects of various NaOH concentrations in CMCm synthesis on the mechanical properties and water vapor permeability (WVP) of the CMCm films were investigated as well. With increasing NaOH concentrations (30–50%) were also found to result in improved mechanical properties. However, when the level of NaOH concentration was 60%, the mechanical properties of the CMC films decreased. This result indicates that the highest mechanical properties were found for 50% NaOH‐synthesized CMCm films. The WVP of the CMCm films increased as %NaOH increased. In addition, the CMCm films were tested to determine the effect of glycerol as a plasticizer on the mechanical properties. Increasing the amount of glycerol showed an increase in elongation at break but also led to a decrease in tensile strength. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Development of a novel antiadhesive material, alginate flakes, ex vivo and in vivo

Postoperative intra-abdominal adhesion sometimes causes significant morbidity. The aim of this study was to compare the efficacy of our newly developed antiadhesive material, alginate flakes, to the most commonly used combination of hyaluronic acid and carboxymethyl cellulose film. Sodium alginate was formed into a gel, powder, or flakes. In the ex vivo study, these different alginate forms were attached onto pig skin and their antisolubility properties in saline and attachment stability were compared. In the in vivo study, a rat surgical adhesion model was used to study the properties of the alginates, and the rats were euthanized on day 14 after surgery. The efficacy of the antiadhesive materials was evaluated using an adhesion scoring system, and the locations that were treated with the antiadhesives were histologically examined. In the alginate groups, the alginate flakes were superior with respect to the antisolubility and the attachment stability ex vivo as well as with respect to the antiadhesive efficacy in vivo. The adhesion score was almost the same as that observed in the alginate flake and cellulose film groups. We developed an alginate flake material and demonstrated its antiadhesive effects both ex vivo and in vivo. This is the first reported study using this flake-like material, which has a unique characteristic in that it can be applied by spraying in compressed air. Alginate flakes may therefore be especially useful in the field of laparoscopic surgery.

Determination of parameters for successful spray coating of silicon microneedle arrays

Coated microneedle patches have demonstrated potential for effective, minimally invasive, drug and vaccine delivery. To facilitate cost-effective, industrial-scale production of coated microneedle patches, a continuous coating method which utilises conventional pharmaceutical processes is an attractive prospect. Here, the potential of spray-coating silicon microneedle patches using a conventional film-coating process was evaluated and the key process parameters which impact on coating coalescence and weight were identified by employing a fractional factorial design to coat flat silicon patches. Processing parameters analysed included concentration of coating material, liquid input rate, duration of spraying, atomisation air pressure, gun-to-surface distance and air cap setting. Two film-coating materials were investigated; hydroxypropylmethylcellulose (HPMC) and carboxymethylcellulose (CMC). HPMC readily formed a film-coat on silicon when suitable spray coating parameter settings were determined. CMC films required the inclusion of a surfactant (1%, w/w Tween 80) to facilitate coalescence of the sprayed droplets on the silicon surface. Spray coating parameters identified by experimental design, successfully coated 280 μm silicon microneedle arrays, producing an intact film-coat, which follows the contours of the microneedle array without occlusion of the microneedle shape. This study demonstrates a novel method of coating microneedle arrays with biocompatible polymers using a conventional film-coating process. It is the first study to indicate the thickness and roughness of coatings applied to microneedle arrays. The study also highlights the importance of identifying suitable processing parameters when film coating substrates of micron dimensions. The ability of a fractional factorial design to identify these critical parameters is also demonstrated. The polymer coatings applied in this study can potentially be drug loaded for intradermal drug and vaccine delivery.

Highly Stable, Edible Cellulose Films Incorporating Chitosan Nanoparticles

The need for biodegradable polymers for packaging has fostered the development of novel, biodegradable polymeric materials from natural sources, as an alternative to reduce amount of waste and environmental impacts. The present investigation involves the synthesis of chitosan nanoparticles-carboxymethylcellulose films, in view of their increasing areas of application in packaging industry. The entire process consists of 2-steps including chitosan nanoparticles preparation and their incorporation in carboxymethylcellulose films. Uniform and stable particles were obtained with 3 different chitosan concentrations. The morphology of chitosan nanoparticles was tested by transmission electron microscopy, revealing the nanoparticles size in the range of 80 to 110 nm. The developed film chitosan nanoparticles-carboxymethylcellulose films were characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis, solubility tests, and mechanical analysis. Improvement of thermal and mechanical properties were observed in films containing nanoparticles, with the best results occurring upon addition of nanoparticles with 110 nm size in carboxymethylcellulose films. Carboxymethylcellulose films containing chitosan nanoparticles synthesized and characterized in this article could be a potential material for food and beverage packaging applications products due to the increase mechanical properties and high stability. The potential application of the nanocomposites prepared would be in packaging industry to extend the shelf life of products.

Potassium ions release from polysaccharide films

In plant growth media of low negative charge, potassium (K) is leached out easily with adverse consequences on its availability to plants and on the environment, since all K fertilizers are completely soluble. The objective of this study was to prepare films based on sodium carboxymethylcellulose (CMC), sodium alginate (SA) and a 1:1 (v/v) CMC:SA mixture to incorporate K and investigate its subsequent release. The film properties were evaluated considering miscibility, glass transition temperature, morphology and permeation of potassium. The absence of strong interactions, the small variation in the glass transition temperature and the roughness detected in the cross-section micrographs of the 1:1 CMC:SA mixtures, indicated a partial miscibility among the components. As a consequence of the above-mentioned characteristics, film release of potassium was highest for the 1:1 CMC:SA mixture and lowest for SA. The release mechanism of K from the 1:1 CMC:SA mixture was controlled by a diffusion process, however, associated effects due to swelling and erosion of the matrix films, were observed for the pure CMC and SA systems. Films of CMC, SA and their 1:1 mixture were able to delay the K release, which can bring considerable benefits in terms of plant growth when media with low negative charges are used.

Synthesis, structural and spectroscopic properties of encapsulated Chlorophyll-a thin film in carboxymethyl cellulose

We report successful retention of the spectroscopic properties of Chlorophyll-a molecules encapsulated in carboxymethyl cellulose acting as an "artificial membrane" material. Films were prepared on indium tin oxide substrates utilizing the spin-coating technique at different concentrations of carboxymethyl cellulose aqueous solution. Results show that the native state of the encapsulated Chlorophyll-a molecules were retained for extended periods of time enhanced further by the optimum concentration effect. Investigations also revealed that the molecules exist in nanocrystal forms with crystal size of 10 nm regardless of the carboxymethyl cellulose concentrations and can be further optimized by varying the spin rates. Chlorophyll-a molecules were found well dispersed in the carboxymethyl cellulose films suggesting the suitability of the gel-like polymer solution as a dispersion agent. It was therefore obvious that the encapsulation of Chlorophyll-a molecules by carboxymethyl cellulose provides prolonged retention of its photoactivity highlighting extended usage when incorporated into future device applications.

Carboxymethylcellulose: A conductivity enhancer and film-forming agent for processable polypyrrole from aqueous medium

The use of carboxymethylcellulose (CMC) in polypyrrole (PPy) synthesis and in the production of PPy freestanding films was investigated. PPy was synthesised by chemical oxidative polymerisation in aqueous solutions using ammonium persulfate (APS) as oxidant and CMC as conductivity enhancer (CMC d). CMCs with different molar weight, namely 90,000 and 250,000 g/mol, were tested. The influence of polymerisation temperature, time, and CMC concentration, on the conductivity of PPy was evaluated thus showing that higher conductivities were obtained at low temperature, short polymerisation time and in the presence of low molar weight CMC. A long time polymerisation study was carried out at 3 °C and 24 °C revealing the presence of a double regime polymerisation process, with second regime rates depending on the polymerisation temperature. CMC was also used to improve the limited film forming ability of PPy by dispersing preformed PPy particles in CMC aqueous solutions. When decreasing the weight fraction of film forming CMC, semiconducting, flexible and freestanding films with thickness of 50–100 μm were obtained and their conductivity increased proportionally to the CMC weight fraction.

Synthesis and optical characterization of ZnS–sodium carboxymethyl cellulose nanocomposite films

In this work, the synthesis and characterization of ZnS–sodium carboxymethyl cellulose nanocomposite films were studied. The film was prepared by casting after the in situ precipitation of ZnS in sodium carboxymethyl cellulose (NaCMC) aqueous solution. The in situ method avoids nanoparticles aggregation and improves its dispersion. The resulting nanocomposite was characterized by X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). The results showed that ZnS nanoparticles with a blende structure and a particle size in the range of few nanometers are well dispersed in the sodium carboxymethyl cellulose films. Optical properties were analyzed by using UV–vis spectroscopy and photoluminescence spectroscopy (PL). The resulting nanocomposite films showed optical transmission between 50% and 90% influenced by the amount of ZnS nanocrystals into the nanocomposite films. The PL spectra of the nanocomposite films exhibits a broad visible emission band centered at 445nm under UV light excitation (λ=320nm). These luminescent films might have a potential application in security paper by using an optical signature.

Use of a film modulator with single-walled carbon nanotubes for mode locking in a pulse titanium-sapphire laser at a wavelength of 810 nm

The feasibility of mode locking in a pulsed laser at a wavelength of 810 nm was shown when a carboxymethylcellulose film with single-walled carbon nanotubes was used as a saturable absorber. With the use of such a film modulator for passive mode locking in the titanium-sapphire laser, a train of continuous-wave ultrashort pulses was obtained. The energy and the duration of a single pulse in the train were 0.4 nJ and 600 fs, respectively.

Physical properties of edible emulsified films based on carboxymethyl cellulose and oleic acid

Glycerol and oleic acid (OA) were incorporated into carboxymethyl cellulose (CMC) films by an emulsification method. Films containing different amounts of glycerol and OA were examined for mechanical properties, water vapor permeability (WVP), and moisture uptake, optical and thermal properties. Addition of OA to the CMC films significantly improved the barrier property. However, the effect of OA on the mechanical properties was lower than glycerol. By increasing of OA content, the cloudiness of the CMC films was intensified and Hunter value (b) of the films increased (by ca. 35.8%).

Impact of edible coatings and mild heat shocks on quality of minimally processed broccoli ( Brassica oleracea L.) during refrigerated storage

The effects of edible coatings and mild heat shocks on quality aspects of refrigerated broccoli were studied. Minimally processed broccoli was coated with either chitosan or carboxymethyl-cellulose with or without a previous application of a mild heat shock of 1.5 min at 50 °C. Product was packaged in multilayered polyolefin bags and stored at 5 °C for 18 d. Quality parameters such as weight loss, texture, colour, ascorbic acid content, total chlorophyll content, oxygen concentration inside the bags, browning potential, mesophilic aerobic counts, and sensory quality, were evaluated during storage. Edible coatings exhibited a beneficial impact on broccoli quality. The weight loss in uncoated broccoli was found to be between 2 and 5 times higher compared to coated samples. During storage, coated florets from both thermally and non-thermally treated samples, presented higher retention of the (− a*/ b*) ratio indicating better green colour retention and a reduced rate of floret yellowing. Chitosan coating always presented the lower ascorbic acid degradation rates (twofold lower compared with control samples). Broccoli texture for uncoated samples increased significantly during storage. However, for carboxymethyl-cellulose coated broccoli a slight increase in texture was observed while for chitosan coated broccoli no significant changes in texture were observed throughout the storage period. After the edible coating application the microbial broccoli load dropped by around 1.5 and 0.9 logarithmic units in chitosan and carboxymethyl-cellulose films, respectively. During storage, the application of chitosan coating significantly reduced total microbial counts in the thermally and non-thermally treated uncoated samples. Among the assayed edible coatings, chitosan effectively maintained quality attributes and extended shelf life of minimally processed broccoli. The single application of a mild heat shock had a measurable influence in reducing weight loss, enzymatic browning in broccoli stems, and in delaying yellowing of broccoli florets. Moreover, chitosan coating combined with a mild heat shock showed the best performance for long-term refrigerated storage of minimally processed broccoli.

Comparative investigations on different polymers for the preparation of fast-dissolving oral films

The aim was to compare different film-forming materials used for the preparation of fast-dissolving oral films. Films were prepared with and without caffeine and caffeine citrate as model drugs. The disintegration/dissolution behaviour of films was investigated using the newly developed slide frame method and Petri dish method. Films were also characterised by dynamic vapour sorption. All films dissolved within 40 s. Drug-loaded films disintegrated more slowly than the equivalent drug-free formulations. Disintegration/dissolution was fastest with films made from the carboxymethyl cellulose C 30 PA 09 (drug-free < 5 s, drug-loaded < 10 s). Dissolution times for drug-loaded oral films made from C 30 PA 09 and HM 6 PA 2910 (hydroxypropyl methyl cellulose) differed significantly (alpha= 0.05). Dynamic vapour sorption studies revealed higher water absorption ratios for carboxymethyl cellulose films, and these were sticky and difficult to handle. This case study showed that hydroxypropyl methyl cellulose was the most suitable film-forming material for drug-free and caffeine-loaded films, providing fast dissolution films that were not sticky and were easy to handle.